Hydraulic long-stroke pump mechanism



May'28, 19-29.- H. M. STAGGS HYDRAULIC LONG STROKE PUMP MECHANISM Filed July 25, 1926 6 a 4 5/ h 4v 2 3 w 2 M 5 2 m w 2 w fimwr r r A??? w n 0/0 i 0% 4 Ww MW d t 6 E m h 3 .irt l} Q. W i

Patented May 28, 1929.

UNITED STATES HORACE M. srAqGs, or snnnvnronr, LOUISIANA.

HYDRAULIC nous-s'rnoxn PUMP MECHANISM,

Application filed July 23,

I This invention relates to hydraulic long stroke pump mechanism, and it comprises a' pumping mechanism for Wells, balanced by the hydraulic action of a fluid contained therein so that loads and strains which areimposed upon the pump operatin mecha nism in use are minimized and alanced. More specifically, my invention consists of a series of three intercommunicating cylinders adapted to contain fluid, a piston in one of said cylinders actuated by movement of the pump operating mechanism, a piston in a second cylinder, of less diameter than the first, connected to a pump rod, and a weighted pis ton in the third cylinder adapted to force fluid therefrom into said first cylinder when its piston is actuated to force fluid into the second cylinder and thus operate the pump, together with auxiliary pumping means in comniunication with a'source of supply for re plenishing fluid which has leaked past the pistons in the respective cylinders by continuously pumping fluid, in small quantities, back to the cylinders from such source of supply, any excess of fluid in the cylinders being withdrawn back to the source of suply. p In long stroke pumping mechanism considerable strain and load is 1mposed upon the walking beam, pitman, and other working parts of a derrick or pumpijack. It is an object of this invention to reduce such strains by a system, which permits a balancing of the forces and loads dueto the rods and fluid within the mechanism itself. A further ob- .ject is to provide a pumping mechanism wherein the force due to the weight of the 'ro'ds receding into the well is' transferred directly through a series of hydraulic cylinders in a self-contained counterbalance without imposing the loads on the walking beam ofrthe mechanism. A still further object is to provide pumping mechanism which operates in a state of hydraulic balance and which utilizes cylinders of unequal size for increasing the stroke ratio of the pump.

Other and further objects will be apparent from the following description and drawing,

in which Figure 1 is a view, partly in vertical section, of the pumping mechanism comprising my invention;

Figure'2 1s a detail sectional view of one of the auxiliary pumps for maintaining a 1925. Serial No. 124,423.

suflicient volume of fluid in the hydrauliccylinders of the pump; and 7 Figure 3 is a detail sectional View of a different form of auxiliarypump, q Referring more particularly to the drawmg: Y

ton 2 therein which is reciprocated by move ment of a walking beam 3, through the medium of a piston rod 4. The cylinder 1 communicates, at its upper end, with a cylinder 5 of smaller diameter in which a piston 6 is reciprocable.v A pump rod 7 is actuated bymovement of the piston 6. The cylinder 1 communicates, at its lower end,with the lower end of a cylinder 8. Y A piston 9 reciprocates in this latter cylinder and has mounted on its upper end a weight 10, guided in-its-move- Piping 13 and 14 leads from the upper ends of cylinders 5 and ,8, respectively, to a source of fluid A, preferably a tank. A pipe 15, also engaged by the means hereinafter described to effect a return supply of fluid from the source of supply to the cylinders. The piston 17 may be held by any suitable means, for exo ample by a spring 18 which surrounds its stem exterior of the cylinder as shown in Fig ure 2, although I do not restrict myself to the use of the specific means shown in the practiceof my invention. The modified formof auxiliary pump shown in Figure 3 comprises a base and an upwardly extending cylinder 16 within which a piston 17 a reciprocates, being spring pressed by a coiled spring ,18 which bears upon the upper end of the cylinder 16 at one end and at its other end upon a washer which encircles the stem of piston 17 Conduits 15 and 28 comprise the inlet and outlet of the pump, and in the respective conduits ball valves 26 and 27 are mounted so that upon upward movement of the piston,17 under the influence of spring 18 ball 27 will seat and ball 26 willbe raised to permit 0 vA mam operating cylinder l carries a pisments by parallel upright members 11 and 12.

and upon downward movement of the iston ball 26 will seat and ball 27 will be li ted to through pipe der 1, whereas auxiliary pump 16 forces fluidpermit the flow of fluid through outlet 28 under pressure.

A second pump 19, similar to. that described, is mounted on the head of cylinder 1 and serves to draw fluid from the source of supply through pipe 20, and to force it 21 into the lower part of cylinof the cylinder shown in Figure 1. The pipe 21 maybe provided with a branch connection leading to the upper part. of cylinder 1 and controlled by a valve 29.

A member 22 is clamped upon the rod l and carries at its ends vertically adustable screws 23 and lock nuts 24:.

In operation, movement of the walking beam upward raises the piston 2, thus forcing the fluid above it into the cylinder of smaller diameter and moving the'piston 6 and pump rod through a substantiallylonger distance. At the same time the counterweight piston 9 moves downwardly to force fluid from its cylinder into the main cylinder, and thus assists the action of the walking into the upper end beam in raising the piston 2. Uponreturn stroke, downward movement of the walking beam moves the piston 2 so that the fiuid beneath it is forced back into the counterweight cylinder thereby raising the piston 9 and counterweight. to their initial positions and at the same time permitting the fluid in the pump rod cylinder 5 to flow back into the main cylinder 1, above the piston, to assist in the downstroke of the piston 2.

As the piston 2 reaches the lower end of its stroke the screws or fingers 23 engage the pistons of the auxiliary pumps, forcing them downwardly. Upon their return stroke additional fluidis drawn from the reserve supply and forced into the main cylinder at each end. \Vhen the system is filled to capacity with the fluid the pistons in the pump rod and counterweight cylinders will be raised to a point where the overflow pipes 13 and 14 will be uncovered. 'When this occurs, any excess of fluid in the system will flow through the overflow pipes back to the source of reserve supply. Thus, a continuous supply of hydraulic fluid is maintained in the system under constant circulation to compensate for any losses which might occur.

From the foregoing it will be apparent that I have provided a simple and elfective systeni for pumping where a short stroke of the operating mechanism results in a relatively long stroke of the pump, and in which a state of hydraulic balance is preserved to absorb shocks and relieve the pumping mechanism of-undue strains and loads. This balance, as will be readily apparent, may be effected initially by completely filling the system with liquid and balancing the weight of the pump gear plus the weight of liquid on the pump side of piston-2 with a counter- .at a constant value.

weight of sufficient heaviness. The reserve system, of course, maintains "that balance against leakage losses.

That I claim is 1. A deep well pump operating mechanism comprising a main cylinder having a piston reciprocable therein, means connected to the piston for actuating the same, fluid passages in communication with the main cylinder on opposite ders, each connected to one of said passages, a piston disposed in one of said auxiliary cylinders means for establishing in each of said auxiliary cylinders a quantity of fluid limited in extent by said main cylinder piston, and weighted meansin the other auxiliary cylinder for maintaining the total energy value of the contents of said auxiliary cylinders constant, whereby, in operation of said first named and main cylinder, a condition of balance may be maintained.

2. A deep'well pump operating mechanism comprising a main pumping cylinder, a piston disposed therein, a piston rod connected to said piston, means attached to the piston sides of the piston, auxiliary cylin- 7 having a connection to a well rod,

rod for reciprocatingthe piston, an auxilthe opposite side of the piston of the main pumping cylinder, a piston therein adapted to reciprocate in accordance with the reciprocation of said main pumping cylinder piston, a fixed quantity of liquid between said last named pair of pistons, and weighted means for equalizing the energy gained by the movement of the fluid in one auxiliary cylinder to the energy lost by a similar movement in the other auxiliary cylinder.

3. A deep well pump operating system comprising three cylinders, fist), a main cylinder containing a reciproca le piston, (19), an auxiliary cylinder communicating with said maincylinder a on one side of the piston, a piston in said auxiliary cylinder 6, a quantity of liquid interposed between said pistons, and means to maintain said quantity at a constant value, (0) an auxiliary cylinder communicating with said main cylinder at and on the other side of said first piston also provided with a piston, a quantity of liquid interposed between said last named pistons, a reserve supply of liquid for the system, pump means communicating with the system and reservesupply to maintain said quantity v4. In a hydraulic pump system, the combination of a main cylinder with two auxiliary cylinders, each in communication with said main cylinder adjacent one of its ends, a pismamas ton in said main cylinder, auxiliary pumps attached to said main cylinder and actuated by the piston of said main cylinder for forcing fluid to said main cylinder at each side of the said piston, a container for a reserve supply of fluid communicating with said auxiliary pumps for maintaining the system complete- 1y filled, and means communicating with the said auxiliary cylinders and reserve supply for permitting flow of excess fluid from the system back to the reserve supply.

5.-In a hydraulic pump system the combination of a main cylinder, and auxiliary cylinders, each 1n communicatlon wlth said main cylinder adjacent one of its ends, a piston in said main cylinder, a rod actuating said piston, an auxiliary pump mounted on said main cylinder, means on said rod for periodically actuating said auxiliary pump, piping connecting said pump with a source of suppl of fluid, and with said main cylinder, an piping communicating with said auxiliary cylinders and with said source of supply for conducting excess fluid from said system back to said sourceof'su'pply.

, In testimony whereof, I have hereunto affixed my signature.

HORACE M. S'lAGGrS.v 

